This invention relates to battery contacts which are used to provide an electrical connection between an electric circuit and a battery. Such contacts generally comprise one portion for coupling to the circuit and a second portion for contact with the battery. In order to maintain adequate electrical connection with the battery, the second portion is often made in the form of a spring which exerts sufficient force against the battery to maintain electrical connection even under stress conditions.
Such springs have normally been made as either leaf springs or helical springs. The leaf-spring version generally consists of a flat, battery connecting portion attached via a bent portion to the circuit-connecting portion, the bend providing the spring effect. The helical spring version generally consists of a round-wire helical spring portion, usually with the helix being in a conical configuration, attached to the circuit-connecting portion. This circuit-connecting portion has also generally been made of round-wire so as to be integral with the spring portion.
A problem with the leaf spring type battery contacts is that they do not readily facilitate the use of different size batteries as they do not exert sufficient force to maintain good electrical contact with a variety of battery sizes. The helical spring type battery contacts are better at facilitating the use of different size batteries but, having round-wire circuit connecting portions renders them difficult to use on automatic assembly lines since it requires very accurate sensing to enable round wire ends to be picked up and positioned by automatic apparatus. Furthermore, such round wire battery contacts cannot be picked up by vacuum operated pick-up arms as there is insufficient surface area for the vacuum to work against.
It is, therefore, an object of the present invention to provide a battery contact which can be used with a wide variety of battery sizes and which can easily be found and handled by automatic assembly lines.